Pneumatic steel making vessels generally include an open-topped, refractory lined steel shell for containing a charge of molten metal. Oxygen gas is commonly delivered to the metallic charge either by a lance or tuyeres which extend through the bottom or sides of the vessel. Hot metal or scrap is initially charged into the vessel through its open top. Vessels of this type are normally supported by a trunnion ring affixed to the vessel and trunnion pins extending outwardly from the ring so that the vessel may be tilted to receive a hot metal or scrap charge and also for pouring molten metal from a tap hole on the upper side of the vessel after the conversion operation has been completed.
Tiltable converter vessels of this type generally have a single tap hole located in an upper portion of the vessel and generally in a plane 90.degree. from the vessel tilt axis. After a period of operation, deformation occurs in the vessel and refractory lining in the area of the tap opening because of the extreme heat and internal refractory loading as a result of the hot metal when the vessel is tilted for tapping and also from the radiant heat of the teeming ladle into which the hot metal is tapped. This deformation in the area of the tap opening is progressive and eventually the refractory in this area must be replaced as a result of its warped contour.
One prior art method of alleviating this problem is discussed in U.S. Pat. No. 3,831,917 and consists of rotating the vessel relative to the trunnion ring. This is accomplished by three support pins arranged equilaterally around the vessel periphery and releasably securable to the vessel for eccentric rotation so that the angle of inclination of the pin may be adjusted relative to the vessel for being coupled to a U-shaped trunnion support in any one of three positions. When this vessel is to be rotated, it is necessary not only to disconnect the vessel support from the trunnion support but it is also necessary to disconnect and rearrange the vessel support pins. This problem is also the subject of U.S. Pat. No. 3,005,628 which discloses a refractory lined vessel which may be elevated and rotated relative to a trunnion ring for purposes of more even wear. In the latter patent, however, the vessel pouring spout is located in a removable cover so that inordinate wear of this portion of the total vessel would not be alleviated by rotation since the cover would always have to remain in the same relative position with respect to the vessel tilt axis.